This is no ordinary heat wave in the eastern U.S., as humidity reaches extreme levels

From New Orleans to Portland, Maine, the heat and humidity has hit oppressive levels for the second long stretch this summer. In New York City, for example, entire blocks smell like hot garbage, and the air feels like a wet blanket, with heat indices approaching 110 degrees Fahrenheit.

While the actual air temperatures during this heat wave are not record-breaking in most areas, it is the humidity that stands out as the weather event's defining feature.